The invention relates to a reactor for the entrained bed gasification of different solid and liquid fuels, comprising an oxidation means containing a free oxygen at normal or increased pressure up to 8 MPa. Solid fuels comprise in this case coal with different coalification degrees which are crushed to form dust, petrol coke and other crushable solids with a heating value of greater than 7 MJ/Nm3. Liquid fuels are understood to mean oils or oil solid or water solid suspensions, such as for instance coal-water slurries. Autothermic entrained bed gasification has been known for many years within the field of gas generation from solid fuels. The ratio of fuel to oxygen-containing gasification means is selected here such that temperatures are reached which are above the melting point of the ash. The ash is then melted down to liquid slag, which leaves the gasification chamber together with the gasification gas or separately, and is then directly or indirectly cooled. Such an apparatus can be found in DE 197 181 31 A1.
A detailed description of such a gasification reactor equipped with a cold screen is found in J. Carl u.a., NOELL-KONVERSIONSVERFAHREN [Noell conversion process], EF-Verlag far Energie and Umwelttechnik GmbH 1996 [EF publishing company for energy and environmental engineering GmbH 1996], pages 32-33. In the conception described therein, a cold screen consisting of gas-tight welded cooling tubes is located inside a pressurized vessel. This cold screen is supported on an intermediate base and can extend freely upward. This ensures that no mechanical stresses can develop with the occurrence of different temperatures as a result of start up and shut down processes and length changes determined therefrom, which could if necessary result in a break-down. To achieve this, there is no solid connection at the upper end of the cold screen but instead a gap between the cold screen collar and the burner flange, which ensures free moveability. To prevent a back flow of the cold screen gap in the case of pressure fluctuations in the system of gasification gas, the cold screen gap is flushed with a dry gas which is free of condensate and oxygen. As practice shows and despite the flushing, the gasification gas flows back, which leads to corrosion on the rear of the cold screen or on the pressure mantle. This may result in operating failures or even in the cold screen or the pressure jacket being destroyed.